1. Field of the invention
The invention relates to a flexible connecting bell for pipes, consisting of a flexible sealing sleeve and a helical spring, which is arranged concentrically to the latter, is designed as a tension spring, has adjacent windings and the inside diameter of which widens or contracts upon opposite twisting of the pipe ends located in the bell, depending on the direction of rotation.
Such a connecting bell is intended for the purpose of being able to connect quickly and gastightly, but also to release quickly, pipes without threaded couplings and without the use of sealing means and without clips.
2. Discussion of Prior Art
In the case of a known connecting bell of this (German Specification No. 806,817), the sealing sleeve also rests directly on the pipe at the joint abutment of the two pipe ends. This sealing sleeve is surrounded by one or more spring windings, which for their part are surrounded by pipe sleeves divided transversely in the centre, the half-parts of which can be twisted oppositely, so that a large radial contact pressure can be exerted on the sealing sleeve. A helical spring with adjacent windings, surrounding the sleeves, has the effect of blocking the sleeves in their twisted position.
The structure of such a connecting bell is complicated due to the many individual parts. The inner sealing sleeve is also not protected against the direct action of the fluid to be conducted through the pipes. In the case of a hot fluid, such as for example, combustion gases of an internal combustion engine, a particularly heat-resistant material is required in order that the sealing sleeve is not damaged by the hot gases. Due to the multi-layered structure, the connecting bell is also relatively voluminous.